When they say it will take them time to implement, it's an honest statement. They literally have to implement software, do lots of code review, check their accounting, pentesting, or at least they should be doing these things, and 5 months is an unusually short timeline. Even if they took 10% as fee to hire extra developers to work on this project, 5 months is not guaranteeable at all.
The short timelines proposed for hard-forks is one of the reasons why so many bitcoin developers have voiced caution about hard-fork proposals: https://en.bitcoin.it/wiki/Segwit_support (far right columns)
Cryptsy was quickly installing random altcoins on their servers until one of the 200 coins they installed ended up being malware (a reverse shell or whatever) and poof goes their exchange, plus or minus some other possible fraud occurring. There is value to caution and review when upgrading software systems.... much less financial systems. With backwards-compatible upgrades, you can be more certain about the net impacts. For example, if the changes were compatible with the pre-existing bitcoin rules, then none of this new coin stuff would have happened, and the whole industry could benefit from the compatible upgrades.