Here is how long it takes on average from the Fremont factory to delivery:
Each quarter, production starts with furthest away destinations and finishes with California. Tesla prefers to deliver Q1 production in Q1 and Q2 production in Q2 because it makes the financials look good in shareholder letters. Therefore, they will now start making HW3 cars for Australia, UK, Japan so they can be delivered within Q2. Then they will continue with HW3 cars for China, Europe, and Canada. Normally HW3 production for the US should start around 10-15 May 2019. Even if we don't see a single HW3 delivery before 20 May 2019, that would be perfectly normal and it would not change the fact that all production switched to HW3 by the end of Q1. However, there is a chance a small number of HW3 cars could be delivered in the US in April.
Each quarter, production starts with furthest away destinations and finishes with California. Tesla prefers to deliver Q1 production in Q1 and Q2 production in Q2 because it makes the financials look good in shareholder letters. Therefore, they will now start making HW3 cars for Australia, UK, Japan so they can be delivered within Q2. Then they will continue with HW3 cars for China, Europe, and Canada. Normally HW3 production for the US should start around 10-15 May 2019. Even if we don't see a single HW3 delivery before 20 May 2019, that would be perfectly normal and it would not change the fact that all production switched to HW3 by the end of Q1. However, there is a chance a small number of HW3 cars could be delivered in the US in April.