diff --git a/.github/actions/latest-version/action.yml b/.github/actions/latest-version/action.yml
index 0bc2b81..3ca0873 100644
--- a/.github/actions/latest-version/action.yml
+++ b/.github/actions/latest-version/action.yml
@@ -24,6 +24,12 @@
 #   # ---> 1.10.13-0
 #   - run: echo ${{ steps.latest-version.outputs.git-describe }}
 #   # ---> 1.10.13-0-g1d2c5aad5
+#
+# Caution: It works smoothly only for 1.10/2.8, but not for 2.10+
+# due to changes in the package versioning (see the new release
+# policy document, [1]).
+#
+# [1]: https://github.com/tarantool/tarantool/discussions/6182
 
 name: 'Latest tarantool version'
 description: 'Get latest tarantool version of given release series'
diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index c7ffec9..ad0b7ed 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -301,3 +301,52 @@ jobs:
         with:
           tarantool-version: '${{ steps.latest-version.outputs.git-describe }}'
           from-cache: true
+
+  # This test case installs tarantool of series-2 using
+  # one/two/three digit version specifier.
+  #
+  # It performs the following steps and checks.
+  #
+  # - install 2/2.10/2.10.0
+  #   - checks: version, non-cached
+  # - uninstall tarantool
+  # - install 2/2.10/2.10.0
+  #   - checks: version, cached
+  test-series-2:
+    strategy:
+      fail-fast: false
+      matrix:
+        tarantool:
+          - '2'
+          - '2.10'
+          - '2.10.0'
+    runs-on: ubuntu-latest
+    env:
+      # github.run_id is the same across different jobs created
+      # from the same matrix.
+      TARANTOOL_CACHE_KEY_SUFFIX: -G-${{ matrix.tarantool }}-${{ github.run_id }}
+    steps:
+      - uses: actions/checkout@v2
+
+      - name: Install ${{ matrix.tarantool }} (non-cached)
+        uses: ./
+        with:
+          tarantool-version: '${{ matrix.tarantool }}'
+
+      - uses: ./.github/actions/verify-version
+        with:
+          tarantool-version: '${{ matrix.tarantool }}'
+          from-cache: false
+
+      - name: Uninstall tarantool
+        run: sudo apt-get -y remove tarantool tarantool-dev tarantool-common
+
+      - name: Install ${{ matrix.tarantool }} (cached)
+        uses: ./
+        with:
+          tarantool-version: '${{ matrix.tarantool }}'
+
+      - uses: ./.github/actions/verify-version
+        with:
+          tarantool-version: '${{ matrix.tarantool }}'
+          from-cache: true
diff --git a/dist/main/index.js b/dist/main/index.js
index 01100cd..61c35e7 100644
--- a/dist/main/index.js
+++ b/dist/main/index.js
@@ -58024,10 +58024,6 @@ const path = __importStar(__nccwpck_require__(1017));
 const fs = __importStar(__nccwpck_require__(7147));
 const nightlyBuild = (core.getInput('nightly-build') || 'false').toUpperCase() === 'TRUE';
 const tarantool_version = core.getInput('tarantool-version', { required: true });
-const tarantool_series = tarantool_version.split('.', 2).join('.');
-const baseUrl = 'https://download.tarantool.org/tarantool/' +
-    (nightlyBuild ? '' : 'release/') +
-    tarantool_series;
 async function capture(cmd, options) {
     let output = '';
     await exec.exec(cmd, [], {
@@ -58081,7 +58077,44 @@ function semver_max(a, b) {
             return pa[i] >= pb[i] ? a : b;
     }
 }
+function construct_base_url() {
+    const parts = tarantool_version.split('.', 2);
+    const major = Number(parts[0]);
+    const minor = Number(parts[1]);
+    var tarantool_series;
+    // Assume that just 2 is latest 2, so it is 2.10+ too.
+    if (major >= 3 ||
+        (major == 2 && minor >= 10) ||
+        (major == 2 && isNaN(minor))) {
+        /*
+         * 2.10+ -- the new release policy is in effect.
+         *
+         * A release series is determined by a major version.
+         * Nightly builds are not provided.
+         *
+         * https://github.com/tarantool/tarantool/discussions/6182
+         */
+        tarantool_series = `series-${major}`;
+        if (nightlyBuild) {
+            throw new Error(`${tarantool_series} does not offer nightly builds`);
+        }
+    }
+    else {
+        /*
+         * 1.10, 2.1, ..., 2.8 -- old release policy is in effect.
+         *
+         * A release series is determined by major and minor
+         * versions. There are release and nightly builds (separate
+         * repositories).
+         */
+        tarantool_series = `${major}.${minor}`;
+    }
+    return ('https://download.tarantool.org/tarantool/' +
+        (nightlyBuild ? '' : 'release/') +
+        tarantool_series);
+}
 async function available_versions(version_prefix) {
+    const baseUrl = construct_base_url();
     const repo = baseUrl + '/ubuntu/dists/' + (await lsb_release());
     // Don't return 1.10.10, when the version prefix is 1.10.1.
     const prefix = version_prefix ? version_prefix + '.' : '';
@@ -58123,6 +58156,7 @@ async function run_linux() {
     try {
         const distro = await lsb_release();
         const cache_dir = 'cache-tarantool';
+        const baseUrl = construct_base_url();
         core.startGroup(`Checking latest tarantool ${tarantool_version} version`);
         const version = await latest_version(tarantool_version);
         core.info(`${version}`);
diff --git a/src/main.ts b/src/main.ts
index 34ba98b..fcbd96c 100644
--- a/src/main.ts
+++ b/src/main.ts
@@ -10,11 +10,6 @@ import * as fs from 'fs'
 const nightlyBuild =
   (core.getInput('nightly-build') || 'false').toUpperCase() === 'TRUE'
 const tarantool_version = core.getInput('tarantool-version', {required: true})
-const tarantool_series = tarantool_version.split('.', 2).join('.')
-const baseUrl =
-  'https://download.tarantool.org/tarantool/' +
-  (nightlyBuild ? '' : 'release/') +
-  tarantool_series
 
 interface CaptureOptions {
   /** optional.  defaults to false */
@@ -78,9 +73,52 @@ function semver_max(a: string, b: string): string {
   }
 }
 
+function construct_base_url(): string {
+  const parts = tarantool_version.split('.', 2)
+  const major = Number(parts[0])
+  const minor = Number(parts[1])
+
+  var tarantool_series
+  // Assume that just 2 is latest 2, so it is 2.10+ too.
+  if (
+    major >= 3 ||
+    (major == 2 && minor >= 10) ||
+    (major == 2 && isNaN(minor))
+  ) {
+    /*
+     * 2.10+ -- the new release policy is in effect.
+     *
+     * A release series is determined by a major version.
+     * Nightly builds are not provided.
+     *
+     * https://github.com/tarantool/tarantool/discussions/6182
+     */
+    tarantool_series = `series-${major}`
+    if (nightlyBuild) {
+      throw new Error(`${tarantool_series} does not offer nightly builds`)
+    }
+  } else {
+    /*
+     * 1.10, 2.1, ..., 2.8 -- old release policy is in effect.
+     *
+     * A release series is determined by major and minor
+     * versions. There are release and nightly builds (separate
+     * repositories).
+     */
+    tarantool_series = `${major}.${minor}`
+  }
+
+  return (
+    'https://download.tarantool.org/tarantool/' +
+    (nightlyBuild ? '' : 'release/') +
+    tarantool_series
+  )
+}
+
 async function available_versions(
   version_prefix: string
 ): Promise<Array<string>> {
+  const baseUrl = construct_base_url()
   const repo = baseUrl + '/ubuntu/dists/' + (await lsb_release())
 
   // Don't return 1.10.10, when the version prefix is 1.10.1.
@@ -125,6 +163,7 @@ async function run_linux(): Promise<void> {
   try {
     const distro = await lsb_release()
     const cache_dir = 'cache-tarantool'
+    const baseUrl = construct_base_url()
 
     core.startGroup(`Checking latest tarantool ${tarantool_version} version`)
     const version = await latest_version(tarantool_version)