Generally, a bond forfeiture would just revoke liberty and have the defendant return to jail pending trial. So no, a bond forfeiture is not analogous to "guilt" or conviction. in lieu of conviction is "in place of" or "instead of," so alone, that is not a conviction either.
In cases where a citation has been issued, the person cited (the defendant) may, with permission of the court, voluntarily agree to waive any court appearances and instead simply agree to voluntarily forfeit the recommended bail amount.
The legal implications of bail bond forfeiture can be severe. Beyond the financial loss, the defendant may face additional charges for failing to appear in court, complicating their legal situation.
If you start communication with both your bondsman and the court as soon as possible, your court date will, in most cases, be reset, and the forfeiture of your bond will be recalled. However, if you do not get back in touch with your bondsman or the courts, the warrant for your arrest will remain active.
In California, a bail bondsman typically has six months to find and return the defendant. If the defendant is not found in the timeframe, you will be responsible for paying not only the full amount of the bond, but also any additional expenses and any unpaid premiums.