Thanks for spelling out why you have taken this Arthur Bostock of the 1901 census at Baginton to be married with Elizabeth Jepson, it all looks right to me now.I have actually taken the 1901 index for Bostocks at Baginton, so I can follow all your remarks, but I haven't looked up the records yet.I go to Kew to do that.
It is actually quite a coincidence to me that we have these two Arthurs who are second cousins, being born within 3 months of each other, at Henbury and Swettenham respectively, and they both marry Elizabeths.At least the 2 Elizabeths are of different ages, 20 and 23 respectively.
Checking for John and Percy in the Birth regs, I can tell you that John is John Ernest, registered Jan-Mar 1899 at Warwick, and Percy was registered Jan-Mar 1901 at Warwick.
John and Sarah are related, but more closely to the other Arthur, who is son of James and Anne.James was born in 1841, and John is a younger brother being born in 1842.
I can't help as to why they moved to Baginton, perhaps the farming was easier there, or the elder brothers inherited the farms in Cheshire.