Setelah memilih versi PHP untuk domain utama anda, selanjutnya merubah versi PHP pada subdomain.
1. Masuk ke cPanel, pilih menu File > File Manager

2. Klik public_html > pilih folder subdomain.

3. cari file .htaccess > klik kanan Edit

4. Tambahkan rule di bawah ini untuk mengubah versi PHP subdomain Anda (contoh di bawah adalah mengubah subdomain ke versi PHP 5.5), kemudian klik Save
<FilesMatch "\.(php4|php5|php3|php2|php|phtml)$"> SetHandler application/x-httpd-alt-php55___lsphp </FilesMatch>

5. Ulangi jika ingin mengubah versi PHP pada subdoman/addon/directory lainnya.
PENTING
Apabila Anda ingin mengubah versi PHP pada file .htaccess, gunakan rule di bawah ini
Versi 5.1
<FilesMatch "\.(php4|php5|php3|php2|php|phtml)$"> SetHandler application/x-httpd-alt-php51___lsphp </FilesMatch>
Versi 5.2
<FilesMatch "\.(php4|php5|php3|php2|php|phtml)$"> SetHandler application/x-httpd-alt-php52___lsphp </FilesMatch>
Versi 5.3
<FilesMatch "\.(php4|php5|php3|php2|php|phtml)$"> SetHandler application/x-httpd-alt-php53___lsphp </FilesMatch>
Versi 5.4
<FilesMatch "\.(php4|php5|php3|php2|php|phtml)$"> SetHandler application/x-httpd-alt-php54___lsphp </FilesMatch>
Versi 5.5
<FilesMatch "\.(php4|php5|php3|php2|php|phtml)$"> SetHandler application/x-httpd-alt-php55___lsphp </FilesMatch>
Versi 5.6
<FilesMatch "\.(php4|php5|php3|php2|php|phtml)$"> SetHandler application/x-httpd-alt-php56___lsphp </FilesMatch>
Versi 7.0
<FilesMatch "\.(php4|php5|php3|php2|php|phtml)$"> SetHandler application/x-httpd-alt-php70___lsphp </FilesMatch>
Versi 7.1
<FilesMatch "\.(php4|php5|php3|php2|php|phtml)$"> SetHandler application/x-httpd-alt-php71___lsphp </FilesMatch>
Versi 7.2
<FilesMatch "\.(php4|php5|php3|php2|php|phtml)$"> SetHandler application/x-httpd-alt-php72___lsphp </FilesMatch>
Versi 7.3
<FilesMatch "\.(php4|php5|php3|php2|php|phtml)$"> SetHandler application/x-httpd-alt-php73___lsphp </FilesMatch>
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