Andre, I’d be guided by Justin’s definition of done criteria for the grade. If you are not quite there yet (and it sounds like maybe you are not quite there yet, based on your comments about C chord) and continuing to consolidate and improve is not going to demotivate you to the point of thinking it is all too much effort, not good enough rate of progress to sustain the hobby with sufficient joy, then I’d keep on keeping on in grade 1 consolidation.
I seem to recall from somewhere that Justin has spoken of consolidation for even as much as 6 months being appropriate.
Re-watching some lessons … can’t hurt.
Stretching by working on some more challenging songs … fine, provided it doesn’t become frustrating.
Given the long-term, never-ending nature of learning and playing guitar, time invested in laying super solid foundations is time well spent. I think developing that ‘it’s a journey and enjoy the present while progressing to destinations without being obsessed on any destination’ mindset is enabling, a growth mindset rather than a fixed mindset (referring to the work of Carol Dweck, about which I shared some thoughts in my own Learning Log here).