Today I was flying, was at about half my maximum altitude, about 60m.  
I flew for a while, returned, and powered the Spark down while leaving everything else on.  I don't usually do this, as I usually only fly one battery at a time.  I put in the new battery and powered up the Spark.  I had to reboot the RC controller to get it to connect (also, if it is relevant, I use OTG).

Once connected, I took off again and was stopped from going past about 25m.  It reported "Maximum Altitude Reached".  I landed, took off again.  Both times it registered GPS mode and RTH location set.  Still blocked from going above 25m.

Landed, turned everything off, turned everything back on, now I could fly up to my normal maximum altitude.  

Anyone had an experience like this?

There are many forum posts about this now. Just check them below.
But short. Close down dji go app and reboot the app before changing battery

And disconnect otg and than connect otg cable into the rc again

YES....same here, swap out 2nd battery and max altitude at 90m, set it at 120m

Glad you solve the problem. If there is anything new and not solved, please let us know. We are willing to help.

@DJI Elektra: what exactly do you mean by "solved"? This is a buggy behavior, we all have to kill/restart the go app if this arbitrary limitation shows up. DJI should investigate what's the problem... there are already so many users here experiencing same issue!

So when is the next firmware release to fix this bad behavior?   

Yes my friend and I both did today 8/29/17.  We both have Spark drones and his restricted flight distance and altitude first. Then mine did the same after I replaced the battery.

Urban flyer Posted at 2017-8-30 17:08
Yes my friend and I both did today 8/29/17.  We both have Spark drones and his restricted flight distance and altitude first. Then mine did the same after I replaced the battery.

Can you test and see if the flight restrictions disappear after you set home point?

DJI Go 4.1.9 just appeared in iOS store...