I put in a ticket for this with Dell and it has been pretty quite about it. In my case though I’m seeing it happen on a certain switch in my test lab the Cisco catalyst 3560-cg series. On this switch the 9.1.5 software am getting a 1 hour ip lease if I roll back the software to 9.1.4 I get a 12 lease and also with all 8.6 thinos. Look at your lease time in the event log but just so you know that pop up will come up every time your device renews the lease and will also stop you from typing and forcing you to click on the screen to make it go in the back ground.
On our normal switches I get a 12 hour lease and it doesn’t matter what thinos I use.