Will upgrade of OS and Informix require recompiling code

We are getting a new p520 soon and I'm expected to put it in production
within 48 hours of getting access to it (great, huh?)

So, anyway we're using BDL 3.50.1a and are migrating from AIX 4.3.3 to AIX
5.3 and from Informix IDS 7.31 to 9.40

Since the "compiled object code" is really not object code, but simply
p-code, should I need to recompile these?

Normally, I would just do it, but given the time frame I'm being given to
work with I'm looking to cut corners wherever possible.  (We're talking
about 2-2.5 million lines of 4GL).

I won't have access to a machine I can test this on until I get the new
production machine.

Thanks in advance.