Fixed-Income and futures settlement question

I recently received an offer from a small buy-side firm. It's a settlements administration job. My current job is in equities operations where I work on the trade life cycle in between execution and settlement. The new role will allow me to continue this plus doing fixed-income and futures booking and settlements. I'm a bit nervous as the interviewer mentioned a past employee worked for a mere week, couldn't get their **** together and was promptly fired. They know I have no experience in fixed-income but I wanted to get out in front of this and see what the difference is in settling fixed-income trades. Is there anything in particular I need to know about coupon rates? Is there any fx function I should know regarding this?

Also, kind of on a side note, I haven't signed the document yet and may have an offer from Blackstone soon for a role that sounds exactly like what I'm doing now, however their pay seems to be a lot more. Am I making the right decision going to the buy-side firm?