Determining appeal rights when in probationary period with prior federal service (break in service)

I am looking for any insight anyone can share on the appeals process for probationary employee illegally terminated. I have been with the federal government for almost 9 months on my current appointment (probationary period would have ended June 1). I was previously with the federal government in a career permanent position 10 years prior (ie I had an 10 year break in service). It is not clear based on 5 USC 7511(a)(1)(A)(i) whether I have full appeal rights or not. I am not sure if I am considered an "employee" because this is not a probation under an "initial appointment".

(a) For the purpose of this subchapter- (1) "employee" means- (A) an individual in the competitive service- (i) who is not serving a probationary or trial period under an initial appointment;

Does anyone have any insight on this?

Also- if I am still categorized as a probationary employee, is it best to file an appeal with MSPB or OSC? To clarify, I got the same template email MANY folks got which falsely indicated my termination was due to performance. I have an OUTSTANDING rating on my performance evaluation and received a performance award.

Any insight or guidance is appreciated.