For me, and I mean it is only me, that job could take me about 2 months. I have a LOT of work, and I work on everyones stuff to get it thru sooner. For just doing the block, 8-9 months does sound long, but is does depend on how busy they are. Hell, I have even had some engines take over a year to complete. Did you make the ultimate customer mistake when you dropped it off and told them "No hurry"? Give them a call, and check on it. Let them know your timeline has changed, and if the could get it out sooner. Diplomacy goes a long way here.
Ask Jim K. and Bart. I did both of theirs, and on the third for Jim, and they know it will take a while. I am the janitor, operator, office lady, customer support liaison, parts manager, financial officer, CEO, equipment repair and maintenance officer, collections department, and much more. All of this before I am the cleaning department, machinist, and assembly specialist. I arrive early, leave late, and barely get to eat lunch.
Anyway, there are many reasons why it takes longer when only one person (or 2) runs the business, but at the end of the day, communication with the customer is key. I love what I do, and I get to bring my dogs to work with me; I wouldn't trade this for any other job...