Who have you spoken about regarding the start of warranty. If you haven't already spoken to Stan in NC (the factory distributor) do so. A delay of commencement between purchase and commissioning can be negotiated within reason. There is usually a proviso though regarding the storage of the engine in this period.
I would have a Beta engine sitting in my garage right now if I could convince Beta to start the warranty clock ticking when it's installed rather than when it's purchased. It's going to replace a Volvo motor. Sometimes I think Volvo could give their motors away and still turn a profit when they sell you repair parts.