I have the same problem using CLI 5.1.1 Runtime 15.
I am getting worried since the deadline is May 9th.
EDIT: Just found out that apps don't stop working on that date but you can't actually update them anymore ( the way it gives the error ).
Is there a fix for this?
I actually released the app just yesterday and the error showed up today.
Pretty concerning if you ask me..
Did read this somewhere on the intel forum tho:
"We recommend that you move to CLI 5.1.1 now so you can prepare for moving to CLI 5.4.1 when it becomes available. CLI 5.4.1 will definitely resolve this issue and it will definitely be available before May 9. Please re-read the original post for full details."
Guess it's just hoping they are on time from now on isn't it?