One would not exactly call this an "Issue" between interest dates. Rather, this is a "Sale" between interest dates. If we "Issue" on March 1 and the first payment comes due on June 30, not only would the first coupon payment be pro-rated for 4 months but also the Discount/Premium amortization portion would be pro-rated for 4 months. Accordingly, the PV of the bond would also change to the PV as of March 1 and not Jan 1. When we issue on Jan 1, but "Sell" on March 1, the PV is still as of Jan 1. Hence, the discount/premium amortization remains unaffected. We just reduce the coupon payment by collecting the accrued portion for which the bond was never held by the bondholder, before-hand Thank you for this video.
Seems like you've made a mistake... you need to discount the first interest payment back 4 months. This should bring the price down of the bond at time of issuance, but seems to be offset by other mistakes you make. The issuance price of the standard bond issuance example should not be used in computing the mid period example. My calculations have issuance price at 493,218.