Changing ISP while keeping services working

Hello,

This is a new one for me, so I am seeking help.

I have a simple setup right now, static IP on the FW, and 3 static IP with DNAT entries (web servers).

We need to change the IP addresses due to an ISP change, but can have both running for a few days.

I have an extra interface ready to configure for the new ISP and connection, but as I change FQDN in my DNS, I need to have the services available on both ISP for a brief time.

Can this be done with Astaro? Have my web server available on ISPA and ISPB but on different interfaces and IP Addresses?