Help! Notice on mat leave

[SquigglyOne]

Right - I’ll try to be clear as possible!
I am currently on mat leave which started on December 1st.
I only receive SMP.
I recently emailed my employer stating I intend to return on 31st August and requesting to go part time - they have acknowledged the email but have not yet said whether I can go part time.
I have now been offered an interview for a new job which I am very interested in.
If I get this job - do I have to give my employer 6 or 8 weeks notice (I’m aware 8 weeks notice is required to change a return date)
Or should I contact my employer now to change the return date to later? So that if I’m successful in securing the new position I can give the full 8 weeks.
Please help - this is making me feel so anxious and confused 😢

[flowery]

You need to give whatever notice period is in your contract.

[gingajewel]

If you are leaving you only need to give your notice period amount not the 8 weeks