As @DianeW777 says, the assets you are describing were placed in service in a prior year, thus there is no adjustment for mid-quarter convention. Mid-quarter convention will only yield a varied depreciation result in the first and last year of the asset's depreciable life. The purpose of mid-quarter convention is to limit your first year of depreciation when you have a large percentage (40% or more) of assets placed int the last quarter. Then, in the final year you will recover the amount you couldn't take in the first year as compared to the half-year convention. No other adjustments are performed.
Here is an article that may help: What's MACRS and MACRS convention?
