Perseus analyses of ἀπόστιχε:

1. ἀποστείχω (go away, go home): aor imperat act 2nd sg
2. ἀποστείχω (go away, go home): aor ind act 3rd sg (homeric ionic)
3. ᾱπόστιχε,ἀποστίζω (mark with points): perf imperat act 2nd sg (doric aeolic)
4. ᾱπόστιχε,ἀποστίζω (mark with points): perf ind act 3rd sg (doric aeolic)

LSJ entries

ἀποστείχω 

ἀποστίζω