Repeating same training within short timespan has the problem of not adding enough new stimulus for your body. Thus you could also try adding a different plan to that 6 weeks. One way would be to do 6 weeks of traditional base before your sweet spot base.
If I’d be you I would be tempted to try something completely different, e.g., between base and build. One option would be to take the traditional base and add some intensity to it. That would provide you with more base, new kind of stimulus and also something that you wouldn’t do otherwise (namely the long slow stuff). This is, however, just my own idea without much evidence.