That being said, if the masters programme is, in fact, reputable,

*and *you also end up doing well in the PhD first-year classes, then it should be serve as more than enough proof of mathematical ability. Therefore, you'll need those grades when you apply. This means that you shouldn't apply in the 2nd year, since those grades aren't out yet, by the time you apply.

The best thing you can do at this point is to self-study and fill in any gaps in your math knowledge to prepare for your masters. Something like

this is really the bare minimum (since it's basically just math camp) that you should know, going into any PhD course. If most of what you see there is very obvious to you, and seem somewhat basic, then you are at a decent spot, in terms of mathematical preparation. Do note that the linked YouTube video series doesn't cover point-set topology (which is usually covered in a typical real analysis class), which you'll need for micro/macro.