Am I missing something atau did Anderson make a big mess up in the time line when menulis Afterlife?? According to the sebelumnya movies&my math at the begining of the movie when it says "four years later" it should be SIX!!???

Alice makes it clear upon meeting up w/ clair again its been a tahun and half sence getting the chopper in the desert. And when finding clair in alaska its six months after the attack on the jepang facility.so from this anda can see it took alice and her clones a tahun to reach japan. If anda do the math w/ the first three films anda know its been 5years allready at the end of extinction.add a tahun and anda got SIX!!!!??