Making some changes to a Blue Prism process I have never seen before

Q: Can we test these changes before going live?
A: No. We are going to pinpoint the problems on the road

Q: Nasty. However we can retry the process if anything goes wrong
A: No. It runs 5:00 to 17:00

Q: Wait, so I have one shot at making this shit work and it's tomorrow?
A: Yes

Yesterday at 2:00 I noticed 2 of the 3 machines are dead, now the process is self destructing every 5 minutes and my mentor, who usually spend weeks without answering phone calls, apparently learned again how do smartphones work 'cause this time he did fucking call.