Based on my experience, way back 2016 i'm about to terminate my plan subscription but, the loyalty department offer me a a better plan below 999 and with a discount and no contract involve nor renewal and for me also to still use or retained the number they provide to me.
Much better call globe hotline 211 using your mobile phone or 02 7301000 when using landline.
I'm not saying that the information provided still accurate up to now.
Plan Zero is no longer offered. I was able to avail plan zero sometime in February 2017 and until now my line is plan zero with 50.00 maintenance fee.