Glimpse of Tomorrow

If the first triggered ability of suspend (the one that removes time counters) is countered, no time counter is removed. The ability will trigger again at the beginning of the card's owner's next upkeep.

You can exile a card in your hand using suspend any time you could cast that card. Consider its card type, any effects that modify when you could cast it (such as flash) and any other effects that stop you from casting it (such as from Meddling Mage's ability) to determine if and when you can do this. Whether you could actually complete all steps in casting the card is irrelevant. For example, you can exile a card with suspend that has no mana cost or that requires a target even if no legal targets are available at that time.

If the spell requires any targets, those targets are chosen when the spell is finally cast, not when it's exiled.

Cards exiled with suspend are exiled face up.

When the last time counter is removed, the second triggered ability of suspend (the one that lets you cast the card) triggers. It doesn't matter why the last time counter was removed or what effect removed it.

A card with no mana cost can't be cast normally; you'll need a way to cast it for an alternative cost or without paying its mana cost, such as by suspending it.