Change in waypoint speed after landing, subsequent takeoff

Flight testing waypoint navigation with 3.5.2. Today I had a route with an intermediate landing and takeoff. The aircraft flew what seemed to be the correct waypoint speed, according to the parameters file prior to the landing and takeoff. After the intermediate takeoff the aircraft flew incredibly slowly. I could walk faster than it was flying.

Anyone else experience this, or have an explanation for the behavior?

I had a similar but somehow different experience. WP_NAV_SPEED was set to 2 m/s and RTH_SPEED was at 5 m/s. An auto mission was done with 2m/s speed then RTH engaged, copter come home with 5m/s and landed, after rearming and starting auto mission again it did the mission with 5m/s… after a power cycle the mission was done at 2m/s again. I was on an assignment so did not had time to reproduce it, so I cannot confirm that this is a constant behavior or I did something stupid. When I’ll have time and weather allows it, I’ll try to reproduce it. however quick glance at the code did not shown any reason for such behavior.