H3 DTC's P 0700/P0751

[Ordieh]

A little over a year ago I had Homer's tranny rebuilt to the extreme (five pinion planetaries,DENALI sunshell,etc.. It has been super sweet. About two weeks ago it started "slam shifting" from first to second at part throttle. Yesterday it threw the codes and leaves from a dead stop in second gear (no first gear). Tomorrow I'm going to replace both solenoids. Hopefully this fixes the problem. Have any of you had a similar experience and wouldn't mind commenting?
Thanks in advance!