[rt2016]

I would wait it out and look for a true software engineer position somewhere else. With a BS from a top school, startup and management experience under your belt you should be a solid candidate for software or product management jobs and shouldn't have to settle for support engineer.

From what I've gathered a support engineer is a combination between a QA engineer and an applications engineer, both of which are considered to be way less technical than a SWE. You likely wouldn't be responsible for new feature development at all as a support engineer.

In general they're not on the same ladder, so it's not a natural transition from support to software engineer. Like you mentioned, you'll have to settle for quite a bit of a pay difference, which will still exist if you transition within the same company. However, if it's absolutely your only way of getting your foot in the door at this company and you're set on working there, it may be something to consider.