Please help me with my exam practice question in Title Ownership in goods.

Shipwrights Boats Ltd (SBL) is in the business of constructing standard model ZZ fibreglass boats for customers. The boats are built to order. SBL has the capacity to work on five ZZ fibreglass boat moulds in its warehouse at a time. Customers pay the purchase price of the boats in instalments as they are being constructed. The boats are built to each customer's specifications with regard to engine size, interior cabin fitout, and colour scheme. The contract terms required BBL to paint the name of each customer's boat on the boat before delivery.

SBL was put into liquidation when it had partially completed five boats for customers, who had each paid varying amounts of the purchase price. Three purchasers had paid the entire purchase price for their boats, which were each 90% complete. The other two purchasers had paid 50% of the purchase price and their boats were each 40% complete. When SBL went into liquidation only one boat, which is 90% complete, has the name "Speedy" painted on its side. The boat names have not been applied to the other four boats. All the boats are still in SBL's warehouse. The contract terms do not state when title to the boats is to pass.

Has the title or ownership of the boats been transferred to any of the purchasers?