Legacy Momentum PLC replacement

I have a question about Momentum PLCs. We need to replace a legacy momentum PLC (171CCC96020) which is acting up. There isn't any type of control narrative for the current system. What is the chance of getting the original program off the PLC and backwards engineering to work on an Allen Bradley or something else... Are there any upgrade paths? For instance to a newer Momentum model, or to a competitor who has a conversion program... Thanks for any help with this! I've never used Momentum before.
According to the Schneider Electric Website ..
171CCC96020 Is replaced by: 171CBU98090 Unity M1E processor

I understand if programmed in ladder logic it will be similar to the Modicon 984 series.
Unlike other PLC's each 'Network' is scanned vertically instead of conventional
left-to-right horizontal. This means the logic particularly mathematical blocks perform
different from what you might expect.
Do you have a copy of your existing program? We can look at it for you. Experienced in Schneider conversions to other systems. Momentum can be programmed in several languages. It helps if you have the program backed up. If not we can step you through it.