We have configured upgrade from one service plan to many different. All of the options appear when you attempt to switch the plan from the providers control panel. but only limited amount (25) is shown when the customer tries to switch the plan from the customers control panel.
The issue is caused by the bug with id #PBA-63494 ("Only 25 plans are shown in switch plan wizard").
Until the bug is fixed, a workaround below can be used:
Create a customization file
<window id="Subscription_ChangeMyPlanList"> <elements> <table id="t1" drop_browse_controls="no" /> </elements> </window>
Restart www for changes to be applied: