This week I got a new offer from a previous company I applied to, which offers me the opportunity to start coding less and less, and slowly prepares me for the job I've always wanted. I would want take the job offer (better pay, and more opportunities), but last week, very unexpectedly, a senior announced his leave, which would leave the company with only 1 junior at the end of november if I would hand in my resignation this month as well.
I know it should be purely business, but this will set back the company quite a bit. I work in quite a specialised field, so it will not be easy for them to find replacements (unless you pay a lot) in a short period of time. I feel really bad about it.
What would you do in my situation? Should I turn down the offer for a few months (until they found a new employee) or is it just purely business and just sign the new contract right now?