funny about multiclass and spellslots

[joaber]

Imagine if I was a lvl 8 Eldritch Knight, with my 2nd lvl spells. Now at lvl 9 PC, I'm multiclassing as a rogue, but since I need to round down my spellcaster lvl, I'll lose the 2nd lvl spells? I'm winning levels but moving back?

Should the paladin and ranger upgrade the spellslots at levels 2, 4, 6... and eldritch knights and arcane trickesters at levels 3, 6, 9... to avoid that problem?

[CNagy]

Imagine if I was a lvl 8 Eldritch Knight, with my 2nd lvl spells. Now at lvl 9 PC, I'm multiclassing as a rogue, but since I need to round down my spellcaster lvl, I'll lose the 2nd lvl spells? I'm winning levels but moving back?

Should the paladin and ranger upgrade the spellslots at levels 2, 4, 6... and eldritch knights and arcane trickesters at levels 3, 6, 9... to avoid that problem?

You don't use the multiclass chart until you have Spellcasting from multiple classes. Rogue1 doesn't give Spellcasting, and by the time you get it at Rogue3, you're going from an 8th level Eldritch Knight spellcasting to a 3rd level multiclass spellcaster (2 from EK, 1 from AT), so you still have 2nd level spell slots.

[joaber]

You don't use the multiclass chart until you have Spellcasting from multiple classes. Rogue1 doesn't give Spellcasting, and by the time you get it at Rogue3, you're going from an 8th level Eldritch Knight spellcasting to a 3rd level multiclass spellcaster (2 from EK, 1 from AT), so you still have 2nd level spell slots.

Forgot the first part. Thank you.