Service Pack Upgrade Compatibility

We have just upgraded to 2018 SP2. Due to server migration and other internal things going on, it took 5 months to go from testing to users desktops - way too long. I believe I know the answer to this, but I'd like to get confirmation...

PDM Server 2018 SP2

Can I upgrade some (heavy hitting structural) engineers to 2018 SP4 only? And leave all other users at SP2, all talking to a PDM client at 2018 SP2? I hope that's enough info to get an answer. Please let me know if I missed something. Thank you.

SolidworksGeneral