Can equipment be moved from a unit it's already attached to, or can you re-equip already attached equipment?

Ruling: You cannot activate equip abilities while the equipment is attached to a unit. All rules text in the upper box of an equipment card (including the equip ability) is turned off while it is attached.

Sequence:

• When equipment is attached, lay the topmost card over it so only the effect text (bottom box) and bonus might appear
• Everything above that (including equip abilities) becomes inactive
• To re-equip, the equipment must first be detached

Nuances:

• Equipment can still be moved by other card effects even while attached (e.g., Weaponmaster keyword, Jax legend, Fluft battlefield, Angle Shot, Relentless Pursuit, Azir Ascendent's activated ability, Akshan for enemy equipment)
• Some effects can detach equipment, allowing you to activate equip abilities again (e.g., Strike Down, Veiled Temple)
• Temporary keyword on equipment only triggers during beginning phase if the equipment is unattached