retrofit query

[Dogboy]

I'm considering retrofitting a bunch of ships. I have enough resources in storage to cover the retrofit. But, I wonder about the order in which acquiring and spending of resources occurs, and could I accidentally leave my existing fleets without support if I hit my economy with a big retrofit.

Say I have 100,000 mineral income and I'm spending 90,000 on maintenance and 10,000 on construction. Net income: 0. Suppose further that I have 50,000 minerals in storage and the cost of the massive retrofit is 50,000 minerals. Will my income arrive first, giving me 200,000 minerals, then 90,000 + 10,000 be spent on maintenance and construction, followed by 50,000 on the retrofit (leaving me with zero stored, but maintenance covered despite retrofit). Or, could the retrofit be taken out of income, leaving me insufficient minerals to cover maintenance, and then I wind up with 50,000 minerals in storage and a bunch of ships falling apart (or rioting? -- actually what happens when they don't get maintenance?)

Also, does retrofitting tie up my ship yards in any way other than taking away from their repair capacity? Can I build more ships at the same time that ships are being retrofit?

Thanks!
DB