RE: Nifty Lipo pack build program...
If you're asking about the voltage diff between the packs (1 volt) when connecting them for parallel charge. Then it isn't an issue. I generally start the lower one first and then the higher one. Many will disagree and want to maintain a minimum voltage differential between all packs before connection. I've heard many different figures for this and have ignored them all.
If you want to know then use a clamp meter and hook the two packs together using your intented parallel setup. Read or log current at the very first start to let us know. (imediately upon connection)