VINE Entertainment made an official statement about the new girl group debut. 
Léa, Dita, Jinny, Soodam, and Denise were supposed to debut on 26th March but their debut is postponed until the situation with coronavirus outbreak will calm down.

Here is the full statement:

Dearest fans of Léa, Dita, Jinny, Soodam, and Denise
On behalf of the members, we would like to first, thank you for your constant love and support. There aren’t words to express the amount of appreciation and adoration they have for each and every one of you. Although the original debut date for the members was March 26th, in consideration of the health and safety of the members, we must announce that due to the worldwide spread of the Coronavirus, the debut date has been delayed until further notice.
Though this news may be unfortunate to hear, our company wishes for nothing more than for the members’ first encounter with every one of you to be in good health, spirit, and environment. Due to this, we, as a company, have come to the unfortunate conclusion to postpone the girls’ long-awaited debut.
In regards to the members’ condition, all of them are in good health and wish to meet with you as soon as possible. We thank you for your patience and understanding. Please continue to show our members your love and support. We look forward to meeting you soon.

Thank you
All the Best,
Vine Entertainment