Whether the speedy trial guarantee of the Sixth Amendment to the U.S. Constitution applies to an accused serving a prison sentence on a prior offense?

Whether for speedy trial purposes under the Sixth Amendment to the U.S. Constitution, the issuance of a formal indictment engages speedy trial protection for an accused serving a prison sentence on a prior offense?

Whether the state can presume that an accused serving a prison sentence on a prior offense has waived by inaction the speedy trial protections of the Sixth Amendment to the U.S. Constitution when the state has not served said accused with the pending indictment?

Whether the speedy trial guarantee of the Sixth Amendment to the U.S. Constitution applies to an accused serving a prison sentence on a prior offense?