Amazing, we're almost in the same boat: I"m also a retired engineer new to HPR, and my L2 flight this past November was similarly a month after my L1 cert! I'm planning next to subsequently develop my DD and redundancy skills, but probably not specifically for L3 since that would require a REALLY large and heavy rocket to avoid busting the local waiver on an M motor. You never know though; there's a NAR/Tripoli prefecture 3 hours away that regularly hosts LDRS events with waivers over 15,000 ft: I've never been there but it's on my list for a visit next summer, COVID permitting.
