It's becoming a ritual with Erdogan's govt recently to launch airstrikes against PKK positions in Qandil, Northern Iraq following every terrorist attack in Turkey that's blamed on militant Kurdish nationalists and they even sent troops to Iraqi Kurdistan last December with the tacit approval of the Kurdish authorities to neutralize PKK militants there.

There's always been tension between Kurdish nationalist factions and they even had a brief civil war[1] between Iraqi Kurds in the 90s (Talabani vs Barzani) and there's rivalry between the Peshmerga and the PKK esp. in the area where the Peshmerga deems its territories in Iraq where some PKK members challenge their authority there but despite all of this, some Kurdish nationalist love to portray the conflict between Turkey and the Kurds as an ethnic and not a political one as it garners more support and sympathy for their cause and make Turkey look like the bad guy in this conflict.

[1]: https://en.wikipedia.org/wiki/Iraqi_Kurdish_Civil_War

Is there any evidence either regarding whether the recent attacks for by Kurds or ISIS?

That's one aspect I find very confusing - Turkish attitudes towards ISIS aren't exactly hardline (eg frequent reports of ISIS supply routes over the Turkish border), and so it isn't clear to me what terror attacks by ISIS in Turkey would gain.

Except terror of course - that's always a thing. And I also understand that ISIS command and control isn't exactly centralised, so it could be random people somewhat aligned.

Another alternative is that they are more tactical in nature - maybe Turkey closes a border route, so ISIS bombs Ankara? I don't know enough to know if this makes sense.

Either way.. confusing.