Auto-open messaging tickets should follow SLA rules instead of first reply time

We've enabled the auto-open ticket for messaging tickets in the omnichannel routing. At this moment we handle all tickets the same, so email + messaging tickets. 

It would be nice if the messaging tickets would be auto-offered to available agents and put into the inbox of an agent on SLA. For example: 

Martin has a maximum of 5 emails and 3 messaging tickets in his inbox. He's always working on SLA's. When he's working on a ticket with a SLA of +54 minutes and a messaging tickets comes in with an SLA of +2 hours, the ticket should be assigned to the inbox of the user instead of auto-opened en overwrites the current ticket due to first reply priority. 

Thanks.