SPRINGFIELD, Mass. (WWLP) – The CDC has updated its guidance about when a person should get the coronavirus vaccine’s second dose.

The recommended time between doses is 21 days for Pfizer-BioNTech’s vaccine and 28 days for Moderna’s vaccine.

However, the CDC now says that while the second dose should be administered as close to the recommended time as possible it can be scheduled up to six weeks later if necessary.