I tried to get more info from an Ally CSR, but if you don't have a maturing CD, they don't disclose much. I was only able to get confirmation that renewal bonuses are possible:
It is a possibility depending on the date of maturity and if you have a qualifying CD.
One reader in my last Ally review mentioned that he was told by the CSR that he could add money to the rollover CD and still receive the 0.50% bump. Another reader mentioned that you could change the matured CD to a new term or the 9-month no-penalty CD and still receive the 0.50% bump. If you have received this retention offer from Ally, please leave a comment about your experience.
It's always a good practice to contact your bank before a CD matures to see if they can offer you a better rate for the renewal. I haven't seen banks, other than Ally, offer 0.50% above their listed rates. A smaller bump of 0.25% is more common (like what PenFed is offering). As I mentioned in my post on the things your bank won't tell you, CD rates are negotiable. So don't let your CDs automatically renew without contacting the bank.