Many of the rebanding questions are answered in the RR WIKI here --> Rebanding - The RadioReference Wiki
What causes issues with scanners and radios are the frequency for some channel numbers were changed. The issue is the frequency for channel xxx prior to rebanding will be one frequency and after rebanding it will be another frequency, so when the trunking system tells the radio to move to one of the changed channels, it will go to the wrong frequency unless the modified frequency table is loaded onto the radio. Newer radios (and scanners) have coding to handle and space reserved for the necessary table(s) while older ones may not.
The RR WIKI articles for the various radio models generally include if a scanner supports rebanding or not. If your scanner does support rebanding, you simply need to change your programming to include the changed frequencies and add the rebanding table information (or simply flag the system as being rebanded, depending on your specific scanner's instructions).
If your radio doesn't support rebanding, all may not be lost since some systems will still work fine and others may generally work, but have a few channels that may not. In those cases your scanner may move to a wierd frequency that's not associated with your system (due to it moving to the old frequency for that specific channel number) and return when that frequency clears up (often quickly since it may not be in use in your area), when the system is done with that transmission, or some combination of the two (depending upon the how your scanner works).
I have a local system that rebanded and only a single channel is one that needs the rebanding table for it to work correctly. On my newer scanners, it works fine once it was reprogrammed. On my older ones that don't have rebanding support, it works fine until that one frequency is in use. The scanner then goes to that wierd frequency for a few seconds and then returns to scan the system normally. I miss a few transmissions, but otherwise it's hard to tell that anything is different.
Another local system has rebanded and every frequency was changed to those that require the rebanding table for it to work right. On that system I can only listen to it using my newer scanners, not my older ones. I am able to program the individual frequencies on the older scanners, but only as conventional channels so the trunking part doesn't work on it and although I can hear the transmissions, they jump around so it's difficult to make sense of the traffic unless the response is quick enough that the system keeps it on the same frequency.