I'm not the op, but in my little app that uses rabbitmq, you have to never assume timely delivery and processing of messages.

I use redis to keep a store of last updated timestamp property (that is, the last time the data was updated), and I essentially throw out a message if the timestamp is older.

For any writing changes I make I have a validation loop in the code path as a secondary validation.

I think once you get used to been defense about incoming messages you can handle most delays