This may not be a bad idea depending what rate of interest is on the bond.
For those who don't know a bond, is a financial certificate which is issued by a firm and bought by an institution or a regular investor. Hence, people give them 600M and this is treated as debt. MUFC has to pay interest to these bond holders (monthly or quarterly). Each bond has a maturity date and when it does mature, they must pay the remaining interest and the full principal of the bond.
Now they are probably issuing a bond because they are struggling to refinance their loans. Hence, they will take the proceeds and pay off the bank loan and thus just have the 600M in bond debt. This can be advantageous if the interest rate is lower than the bank loan (so we pay less interest). On the flip side, it could have a higher interest rate and we could be paying more interest because they cannot meet their payments and are just looking to delay it.
Unfortunately, I don't know much about how interest is set or if a bank loan would be cheaper or bonds. Anyone a specialist about interest rates?